Bernie Ecclestone told the high court in London on Monday: "I have a bit of a difficulty to remember what happened last week." The Formula One chief executive, who was 83 last month, was facing his fourth day of questioning in the case brought by Constantin Medien.

The German media company claims that Ecclestone undervalued Formula One when it was sold to the private equity group CVC Capital Partners and that he colluded with the German banker Gerhard Gribkowsky – who was jailed last year for eight and a half years – to keep control of the sport. Ecclestone denies wrongdoing.

Constantin Medien is claiming $141m (about £88m) in damages from Ecclestone – who has run F1 for almost 40 years – and three others in the court case which opened last week.

At one point Philip Marshall QC, representing Constantin Medien, asked a question about Bambino Holdings, Ecclestone's family trust, which referred to 2002. Ecclestone replied: "I'm learning a lot, for which I thank you, because this was 12 [sic] years ago. I have a bit of difficulty to remember what happened last week."

Earlier, when asked about CVC's purchase of a controlling interest in Formula One in 2005, a hesitant Ecclestone replied: "By the look of this I – dates – I'm sorry, I can't keep up with these days."

Ecclestone also had difficulty remembering a meeting he allegedly had last year, at the time of the jailing of Gribkowksy. Ecclestone and three other parties are accused of paying $44m in bribes to Gribkowsky to undervalue F1 when it was sold to CVC.

But when asked about the meeting, Ecclestone, after a pause, replied: "I don't remember what the meeting was for but, if you – I don't remember the meeting but, if you said – I have hundreds of meetings a month but, if you said there was a meeting, there obviously was a meeting but I don't remember what it was for."

Ecclestone said outside court that he is innocent. Asked whether he maintained his innocence, he said: "Absolutely. You have to live with all these things. These people are there doing a job. Some people trying to win a case say what they think is the right thing to say to win the case."

Asked whether the case is damaging for Formula One, Ecclestone said: "I don't think so. It's good because a lot of facts come out of it."

Asked where he would be going now, he replied: "Austin, USA." The penultimate race of the season takes place in the capital of Texas on Sunday, followed by the last round in Brazil the following weekend. The case continues.